1. Field of the Invention
The present invention relates to an electrical connector for electrically connecting an electronic package such as a land grid array (LGA) chip with a circuit substrate such as a printed circuit board (PCB), and particularly to an electrical connector with terminals each having a plurality of retention protrusions.
2. Description of the Prior Art
Land grid array (LGA) connectors are widely used in personal computer (PC) systems to electrically connect LGA chips with PCBs. An LGA connector comprises a multiplicity of terminals arranged in a rectangular array. Each terminal has a first contact portion soldered to a PCB, and a second contact portion depressed by and engaging with a corresponding contact pad of an LGA chip. Thus the chip and the PCB are electrically connected by the connector.
China Pats. Nos. ZL95223360.6 and ZL0221158.3, and U.S. Pats. Nos. 6,296,495 and 5,984,693 each disclose a conventional terminal of an LGA electrical connector. Referring to FIG. 8, U.S. Pat. No. 6,296,495 discloses a terminal 5 of an LGA electrical connector. The terminal 5 is stamped from a resilient metal strip. The terminal 5 comprises a horizontal soldering base 50, for soldering the terminal 5 to a circuit pad of a PCB (not shown) and thereby electrically connecting the terminal 5 with the PCB. The soldering base 50 has a rear end 501 and a front end 503. An upper spring arm 52 extends upwardly and forwardly from a rear end 501 of the soldering base 50. The spring arm 52 has a curved top contact portion 521 for engaging with a plate-like contact pad of an LGA chip (not shown) when the LGA chip is pressed against the LGA electrical connector. Thus, the terminal 5 electrically connects the LGA chip with the PCB. A lower beam 54 upwardly and forwardly extends from a front end 503 of the soldering base 50. A vertically oriented junction portion 56 extends from a front end of the lower beam 54. An upper section of the junction portion 56 is bifurcated, and forms a pair of retention arms 561. The lower contact beam 54 and the junction portion 56 are integrally joined between the retention arms 561. A multiplicity of barbs 562 is respectively formed on opposite vertical side edges of the junction portion 56, for interferentially fixing the terminal 5 in an insulative housing (not shown).
However, the barbs 562 are so thin that the terminal 5 is liable to sustain deformation in assembly of the LGA electrical connector. In addition, the horns of the barbs 562 are prone to scrape inner surfaces of a corresponding passageway of a housing (not shown) of the LGA electrical connector, resulting in the terminal 5 not being securely fastened in the passageway. These contingencies can lead to failure of electrical connection between the LGA chip and PCB.
A new LGA electrical connector which overcomes the above-mentioned problems is desired.
An object of the present invention is to provide an electrical connector having terminals securely fixed in a housing thereof.
In order to achieve the above object, an electrical connector in accordance with the present invention comprises an insulative housing and a plurality of terminals. The housing defines a plurality of passageways receiving the terminals therein. Each passageway comprises a retention space that is bounded by a forward wall, a pair of side walls and a pair of rearward walls. Each terminal comprises a vertical retention portion, and a connection beam extending from the retention portion. The connection beam has a first contact portion for soldering the terminal to a circuit substrate. A spring arm extends upwardly from the first contact portion. The spring arm defines a curved second contact portion. The retention portion comprises a first main face, a second main face, and a pair of side faces. A retention protrusion extends outwardly from each of opposite sides of the retention portion, and then bends perpendicularly.
In a first preferred embodiment of present invention, the protrusions protrude beyond both the side faces and the second main face of the retention portion. Each protrusion comprises a first interference portion parallel to the respective side face, and a second interference portion parallel to the second main face. The first interference portions of the protrusions interferentially engage with the respective side walls of the corresponding passageway, and the second interference portions of the protrusions interferentially engage with the forward wall of the passageway. The protrusions each have a reinforced structure, and the terminal is securely and reliably retained in the passageway. Second and third preferred embodiments of the present invention are also shown and described.
Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: